The fossil of a completely new species recently discovered in China has revealed the truth about one of the most bizarre lineages of monsters in the world.
According to Sci-News, this is an extremely ancient ancestor of the plesiosaur, marine reptiles with necks that were even longer than the rest of their bodies.
The fossil, uncovered from the Nanzhang-Yuan’an ancient animal site in Hubei Province, China, dates back to 248 million years, marking the beginning of the Triassic period, which was the first era in the explosive age of giant reptiles spanning the Triassic, Jurassic, and Cretaceous periods.
Diagram showing how ancestral monsters rapidly evolved to create the group of bizarre plesiosaurs – (Photo: Qi-Ling Liu).
“The early Triassic was a period marked by rapid evolutionary processes in marine life following the devastating mass extinction at the end of the Permian. This era was particularly characterized by the emergence of new animal species and new ways of living,” explained Dr. Qi-Ling Liu from Wuhan University of Geosciences (China).
The ancestor of the plesiosaur has been named Chusaurus xiangensis, belonging to the group of pachycephalosaurs, with a neck significantly shorter than many later “descendants,” according to a publication in the journal BMC Ecology and Evolution.
This group of monsters is exactly the connection that biologists have long sought: the group bridging the eosauropterygian – an ancient group of short marine reptiles – and later plesiosaurs.
Chusaurus xiangensis is the shortest-necked pachycephalosaur known, but it clearly shows the evolutionary trend of neck elongation.
Combined with other fossils from the same group, it presents vivid evidence that plesiosaurs inherited their bizarre body shapes from ancient ancestors by gradually adding new vertebrae over generations.
The longer neck became more flexible, allowing them to capture prey with agility similar to that of a snake while maintaining a stable body shape.
With the emergence of what are considered true plesiosaurs in the following Jurassic period, it is evident that this ancestral group evolved extremely rapidly, particularly in neck elongation. This rapid evolution may have been stimulated from the start by the harsh post-extinction world in which they emerged.
